Electrical connecting device having opposed annular surfaces frictionally engaging wire



25, 19 64- 5, ZAUGG 3,122,605 NC DEVI ELECTRICAL GONNECTI CE HAVING OPPOSED SURFACES FRI'CTIONALLY ENGAGING WIRE Filed Feb. 3. 1963.

3,122,605 ELECTRICAL coNNEcrrNG DEVICE HAVING OPPOSED ANNULAR SURFACES Farc'rroN- ALLY ENGAGING WHQE Samuel Zaugg, Soleure, Switzerland,asignor to Brevets Aero-Mecaniques S.A., Geneva, Switzeriand, a society of Switzerland Filed Feb. 3, 1951, Ser. No. 87,008 Claims priority, appiication Switzerland Feb. 22, 1960 2 Claims. (Cl. 174-94) The present invention relates to devices for making an electrical connection between a terminal and a conductor Wire. There are known devices of this kind in which the conductor wire is forced between two surfaces of the terminal so as to be deformed by these surfaces to ensure a good electric contact therewith. In these known devices, said surfaces are generally two ridges forming the edges of a slot, often V-shaped. Such terminals are relatively bulky and are not suitable for use in electrical circuits of small dimensions.

The object of the present invention is to provide an electrical connecting device which is both simple and of small size.

The device according to this invention is characterized in that the terminal is of general cylindrical shape and comprises two annular parallel surfaces between which the conductor wire can be forced, the planes of these annular surfaces being perpendicular to the axis of the terminal.

A preferred embodiment of the present invention will be hereinafter described with reference to the accompanying drawings, given merely by way of example and in which:

FIG. 1 is an axial sectional view of a terminal according to the present invention intended to receive two conductor wires, this terminal being mounted in a plate of an insulating material.

FIG. 2 is a plane view of this terminal showing the conductor wires before they have been connected to the terminal.

FIG. 3 is a view similar to FIG. 1 showing the wires connected to the terminal.

FIG. 4 is a view showing wire pliers for fixing the wires to the terminal.

FIG. ;1 shows a plate 1 of an insulating material, which may be thermoplastic, provided with a hole 2 adapted to accommodate a cylindrical pin 3 carrying two circular flanges 4 and 5. The bottom end 6 of pin 3 is of frustoconical shape to facilitate the introduction of this pin into hole 2, the diameter of which is slightly smaller than that of the pin.

- The two respective surfaces 7 and 8 of flanges 4 and 5 that are located opposite each other are of annular shape. They constitute parallel surfaces the distance between which is slightly smaller than the thickness of the conductor wire to be mounted on the terminal. In the embodiments of FIGS. 1-to 3, conductor wires 9 and 10 are of circular cross section, so that the distance between annular surfaces 7 and 8 is slightly smaller than the diameter of these wires.

In order to connect wires 9 and 10- with terminal 3, the bared ends of these wires are first placed in the position shown by FIG. 2. Each wire is located opposite the groove formed between flanges 4 and 5 and at a small distance therefrom, as indicated in FIG. 1 for wire 10.

The two conductor Wires 9 and 10 are then forced be- United States Patent 0 'f atented Feb. 25, 1964 tween flanges 4 and 5, for instance by means of the pliers shown by FIG. 4. This tool comprises two end portions 11 and 12 having surfaces 13 and 14 respectively intended to be applied against corresponding portions of the periphery of flanges 4 and 5. After wires 9 and 10 have been pushed by the pliers, a portion of these wires is tightly held between flanges 4 and 5 after having undergone a slight deformation.

Each of the wires is secured in position by the pressure exerted thereon by flanges i and 5 due to the elasticity preserved by the wire after its deformation.

Wires 9 and 10 are therefore fixed to terminal 3 in a safe manner without necessity of heating terminal 3 to perform welding. It follows that plate *1 is not injured, even if it is made of a thermoplastic resin.

It should be well understood that the body of general cylindrical shape of the terminal is to be provided with at least two substantially parallel annular faces at a distance from each other smaller than the thickness of the conductor wire, such faces being obtained in any of different ways. Furthermore, the annular surfaces are not necessarily located on the outside of the cylindrical surface of the terminal body. The tool used for inserting the conductor wire between the two parallel faces may be of any kind whatever but advantageously it comprises two active elements having each a portion of cylindrical shape intended to be applied against a portion of the periphery of flanges 4 and 5 or of the cylindrical wall of the terminal when said terminal is only provided with a peripheral groove for fixation of the conductor 5.

The device according to this invention is very advantageous in the case of small apparatus in which the cross sectional area of the conductor wires is nearly always much greater than required by the intensity of the current flowing through these wires.

To facilitate the insertion of the wire between the two parallel surfaces, the edge of each of these surfaces might of course be rounded.

What I claim is:

1. An electrical structure which comprises, in combi-- nation, a terminal of a conducting material having a portion thereof of general cylindrical shape provided with other'and perpendicular to the axis of said cylindrical portion, and a conductor wire of a diameter greater than the distance between said annular flanges, a portion of said wire being squeezed between said annular flanges, said wire portion being flattened to hold with a forced fit therebetween.

References Cited in the file of this patent UNITED STATES PATENTS 1,673,086 Lundberg June 12, 1928 ,7 2,501,187 Oortgijsen Mar. 21, 1950 3,009,985 Trussell Nov. 21, 1961 

1. AN ELECTRICAL STRUCTURE WHICH COMPRISES, IN COMBINATION, A TERMINAL OF A CONDUCTING MATERIAL HAVING A PORTION THEREOF OF GENERAL CYLINDRICAL SHAPE PROVIDED WITH TWO PARALLEL FLAT ANNULAR SURFACES DISPOSED OPPOSITE EACH OTHER AND PERPENDICULAR TO THE AXIS OF SAID CYLINDRICAL PORTION, AND A CONDUCTOR WIRE OF A DIAMETER GREATER THAN THE DISTANCE BETWEEN SAID ANNULAR SURFACES, A PORTION OF SAID WIRE BEING SQUEEZED BETWEEN SAID ANNULAR SURFACES, SAID WIRE PORTION BEING FLATTENED TO HOLD WITH A FORCE FIT THEREBETWEEN. 